Fueling issues, dual cp3 belt slip, maxed out 165?

LSxBakakos

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Last year I tried out my big tune at the track. 100rw didn't even net me a tenth, literally hundreths. Wot on the big tune is fine until about the 1000ft mark, then it's a gamble whether its freight training or spitting/sputtering. Realized this happened after the violent launch that broke my sending unit. I'll be replacing within the next week or so with the fleece sureflo and most likely going AN line rather than the airdog hose

During "winter hibernation" I replaced the idlers/tensioner, serp because the truck developed a belt chirp. During this time I realized the smooth idlers had rubber transfer on them indicating slip. Retrued/straight edged the pulleys as well(seems to have moved a little) Debating on buying the dhd manual tensioner and additional idler support pulley, thoughts?

Lastly i realized airdog doesn't indicate whether their max hp rating is for flywheel or rw. I spoke with a tech which asked pressure and so on, didn't get a direct answer. My truck makes around 750 to the tire, with drivetrain loss that would put me well over 800 flywheel. Is it time to go 220?

Ive tried numerous times on the street to get a data log. In 2wd I can't get it to replicate the problems to better pinpoint. I know the truck will starve itself on fuel on a hard launch or pull if it's around 5/8. Otherwise it's a guessing game lol

Interested to see what you guys have to say

Thanks in advance

T.J.
 

2004LB7

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Moved to fuel systems

I think most solved slipping on the dual CP3 with a manual tensioner
 

LSxBakakos

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Moved to fuel systems

I think most solved slipping on the dual CP3 with a manual tensioner
Thank you sir

Considering it's price tag I figured it was worth asking. Figured maybe its worth it to re-pin the tensioner, no idea. All i know if I were to do it again, id just do a stroker pump
 

2004LB7

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Thank you sir

Considering it's price tag I figured it was worth asking. Figured maybe its worth it to re-pin the tensioner, no idea. All i know if I were to do it again, id just do a stroker pump
A stroker is a very good option today. Long gone are the issues that plagued the earlier versions
 

Bdsankey

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It sounds like you have more diag to do.

Personally a 165 "shouldn't" be your limiting factor at this exact moment. My 160k mile AD2 165 made 870whp in 4x4 on Duramax Tuner's dyno. The easiest way to tell is to watch inlet pressure at the CP3(s). If it's falling tremendously you either have a flow issue (too small of a lift pump) or a supply problem (too hard for the lift pump to pull fuel from the tank/restriction there).

What is your log showing? Is your data log showing the pumps going to full fuel and simply unable to keep up with demand or does it recover?

Can you also fill out your signature so we know what mods the truck has?
 

LSxBakakos

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It sounds like you have more diag to do.

Personally a 165 "shouldn't" be your limiting factor at this exact moment. My 160k mile AD2 165 made 870whp in 4x4 on Duramax Tuner's dyno. The easiest way to tell is to watch inlet pressure at the CP3(s). If it's falling tremendously you either have a flow issue (too small of a lift pump) or a supply problem (too hard for the lift pump to pull fuel from the tank/restriction there).

What is your log showing? Is your data log showing the pumps going to full fuel and simply unable to keep up with demand or does it recover?

Can you also fill out your signature so we know what mods the truck has?
Didnt know you were local man! Unless I'm in 4x4 on the track I can't not get it to replicate it on the street no matter what I do. The prior logs I had had DFPR and AFRP and they were dead nuts. I know for a fact I was getting belt slip on the dual fueler belt so I'm hoping this is part of the issue. I'll have to see if my scanner will pick up inlet pressure unless that's a mechanical ordeal.

It's been a hot minute since i tried filling out the signature, ill give it a go though

Ive made 800+ on a single 165. Doubt thats the issue. I do use a ppe pickup in a factory sump though.
That's also good to know between you and bdsankey that you've made more than 800 on a 165. I'm hoping the sureflo also helps this issue since I've had oddball starvation issues before.
 

2004LB7

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Didnt know you were local man! Unless I'm in 4x4 on the track I can't not get it to replicate it on the street no matter what I do. The prior logs I had had DFPR and AFRP and they were dead nuts. I know for a fact I was getting belt slip on the dual fueler belt so I'm hoping this is part of the issue. I'll have to see if my scanner will pick up inlet pressure unless that's a mechanical ordeal.

It's been a hot minute since i tried filling out the signature, ill give it a go though


That's also good to know between you and bdsankey that you've made more than 800 on a 165. I'm hoping the sureflo also helps this issue since I've had oddball starvation issues before.
Mechanical deal. No sensor for inlet pressure
 

LSxBakakos

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Mechanical deal. No sensor for inlet pressure
Thank you sir. What's the process for this? And I'd imagine I'd test off of the valley pump vs the secondary cp3? Or will it not matter since both pumps split the load? Only issue that still remains is the lack of being able to replicate it on the street. Then again can always try to do it at the track worst case scenario
 

2004LB7

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Thank you sir. What's the process for this? And I'd imagine I'd test off of the valley pump vs the secondary cp3? Or will it not matter since both pumps split the load? Only issue that still remains is the lack of being able to replicate it on the street. Then again can always try to do it at the track worst case scenario
jkfuelpressure06c[1].jpg
 

LSxBakakos

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Guess I'll have to buy a new one before I can test lol. My shrader valve was leaking so I've got the dhd brass plug in that port. Hopefully I can find what parameters I should be at there
 

Bdsankey

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You can add a sensor/gauge anywhere in the low pressure side near the CP3s. It can be a hose barb union with a 1/8npt port that you put a plug in later, just something to see what supply pressure is under load.

Personally I'm betting you've got a pickup issue where it's starving for fuel.
 

LSxBakakos

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You can add a sensor/gauge anywhere in the low pressure side near the CP3s. It can be a hose barb union with a 1/8npt port that you put a plug in later, just something to see what supply pressure is under load.

Personally I'm betting you've got a pickup issue where it's starving for fuel.
Thank you sir, I appreciate it. My gut has said since it's been a starvation issue so well see where that built in draw straw in the fleece gets me and go from there
 

Bdsankey

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Thank you sir, I appreciate it. My gut has said since it's been a starvation issue so well see where that built in draw straw in the fleece gets me and go from there
Is there a reason to go with the Fleece unit instead of others that are available for 1/3 to 1/2 the price like the PPE kits?
 

LSxBakakos

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Is there a reason to go with the Fleece unit instead of others that are available for 1/3 to 1/2 the price like the PPE kits?
Originally I was going to sump it. The fleece utilizes either stock quick connects or AN fittings and apparently will support 1200rw without cavitation and without cutting up the stock tank. With future goals of 1000rw and not having to "modify" the tank it seemed like the best route for myself and my goals. It's actually a nice piece, all billet construction too
 

Bdsankey

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Originally I was going to sump it. The fleece utilizes either stock quick connects or AN fittings and apparently will support 1200rw without cavitation and without cutting up the stock tank. With future goals of 1000rw and not having to "modify" the tank it seemed like the best route for myself and my goals. It's actually a nice piece, all billet construction too
I'd make an argument that the PPE solution is better value unless you need a new sending unit. The Fleece sureflo is a great product that is definitely a go to piece for customers needing a new sending unit and who want the ability to run a lift pump etc but I don't know if it's the best "bang for the buck".



PPE's kit for 01-05 is larger (5/8 pickup) and roughly 1/2 the price using the OEM sending unit so no cutting of the tank.

PPE's kit for 06-08 is 5/8 and less than 1/3 the price of Fleece using the OEM sending unit as well

PPE's kit for 09-10 is 5/8 and less than 1/2 the price of Fleece
 

LSxBakakos

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I'd make an argument that the PPE solution is better value unless you need a new sending unit. The Fleece sureflo is a great product that is definitely a go to piece for customers needing a new sending unit and who want the ability to run a lift pump etc but I don't know if it's the best "bang for the buck".



PPE's kit for 01-05 is larger (5/8 pickup) and roughly 1/2 the price using the OEM sending unit so no cutting of the tank.

PPE's kit for 06-08 is 5/8 and less than 1/3 the price of Fleece using the OEM sending unit as well

PPE's kit for 09-10 is 5/8 and less than 1/2 the price of Fleece
I'm sure there's better options, this worked for me. Im unsure if the float stuck empty, or if it broke during my violent launch. Either way I did need a new sender(and have a brand new delco at home if anyone needs it). This as well is a 5/8 straw but as you stated is the more expensive route. I'm just hoping this solves the starvation issue at hand, i do believe there was a video on launch showing the slosh issue that you commented on back then. None are visible from the 1000ft mark of it spitting. All I know is 100rw should've netted me more than hundreths lol
 

Chevy1925

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Honestly I’d try to replicate the issue. Could be throwing money at something that wont fix it.

Do you have a pic of your time slips, the one before you bumped power and one after? Curious if you really gained anything before the 1000ft mark.